Well, but it's not even clear, what is his connection to the eatery. However, there will be some because of the name. Siberian (Engl) or Siberyak(russ).
My guess he doesn't have even a work permit, what leads to the question why so many Russians are caught doing illegal things here and how they can do it? By bribing or just ignore Thai laws? Many it seems to me are not here for holidays but permanent living. I'm not amused.π€